Gas-engine.



No. 823,450. PATENTED JUNE 12, 1906.

' B. P. STEWART.

GAS ENGINE.

APPLICATION FILED PEB.10. 1905.

3 SHEETS-SHEET 1 56/ ye/14a? i i 576a (of ir/y N0. 823,450v PATBNTED JUNE 12, 1906. B P. STEWART.

GAS ENGINE.

APPLICATION FILED FEB-10. 1905.

3 SHEETS-SHEET 2.

No. 823,450. PATENTED JUNE 12, 1906. B. F. STEWART.

GAS ENGINE.

APPLICATION FILED FEB. 10. 1905.

3 SHEETS-SHEBT 3 4; h y/mm; AQF/mz (U/A UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

Patented June 12, 1906.

Application filed February 10, 1905. Serial No. 5,0

.To all whom it may concern:

Be it known that I, BENJAMIN F. STEwAIiT, a citizen of the United States, and resident of Chicago, county of Cook, and State of Illinois, have lnvented certain new and useful Improvements in Gas-Engines, of which the folowin is a specification, and which are illustrate in the accompanying drawings, formingra part thereof.

he invention relates to a two-cycle ty e of gas-engine in which provision is made or the partial compression of the air for each charge before the introduction of the combustible material, the latter being preferably delivered to the passage through which the char e enters the cylinder.

The object of the invention is to provide means for regulating the supply of air admitted for each charge and of automatically varying the amount of fuel delivered, so that it will be proportional to the air-charge.

A further object of the invention is to improve the construction of engines of this type, as Will appear in the following description.

The invention consists in the construction and arrangement of parts to be hereinafter described, and which are illustrated in the accompanying drawin s, in which Figure 1 is a side elevation of an engine constructed according to the invention, some of the parts appearing in central longitudinal section. Fi 2 is a vertical cross-section of the same. Fig. 3 is an elevation of a detail shown in Fig. 2. Fig. 4 is a view similar to Fig. 3, but having some of the parts removed. Figs. 5 and 6 are sectional views on the lines 5 5 and 6 6, respectively, of Fig. 2.

In Fig. 1 of the drawings is shown an engine having two cylinders 10 and 11, so much of the walls of each of which as surround the combustion-chamber being provided with a plurality of ribs 12 for increasing the radiatin -surface. equally applicab e to engines having but one cylinder and to those having more than two cylinders, and since in any case the cylinders are essentially alike the dcscri tion will be confined generally to but one. The cylindercasting continues to the line of the crankshaft 13, where it is joined by bolts 14 to a base 15, so chambered as to form with the lower portion of the cylinder itself a housing for the crank 16. Straps 17 are secured by bolts 18, assing through the cylinder-walls to the body of the engine, and serve for se- The invention is curing it to any suitable foundation. The piston is shown at 19, and 20 indicates a itman for connecting it to the crank 16. The crank-chamber formed'within the base 15 and lower portion of the cylinder-casting,.as previously described, constitutes the primary compression-chamber and communicates with passages 21-and 22, cored into the cylinder-walls, one of which, as 21, serves for the introduction of the air-sup ly for each charge. The other passage 22 orms a communication between the primary compression-chamber and the interior of the cylinder and opens into the latter through a port 30, which is uncovered by the iston 19 when near the limit of its outstro e. The fuel is preferably delivered to that part of the primary compression-chamber which constitutes the latter passage.

A threaded opening 23 is provided in the outer wall of the passa e 21, and into this opening is secured a va ve-casing 24, carrying a puppet-valve 25, opening inwardly and having a threaded stem 26 projecting out through the casing. A plurality of air-openings 28 are formed in the face of the casing, and the passage of air through these openings may be regulated by a damper 29, correspondlngly apertured and turning about the valve-stem 26. A spring 27, coiled about the valve-stem and reacting between a set-nut carried by the stem and the damper 29, serves to seat the valve 25 and cause the damper to frictionally engage the face of the casing.

For introducing the fuel there is provided a casing 31, secured to the cylinder-wall and opening to the passage 22. This casing is provided with a tube 32, extending throu 1: its body and ada ted at its outer end to e connected with t e fuel-suppl The inner end of the tube extends into t e chamber of the casing and is piovided with a small lateral opening 33, w 'ch is normally closed by a needle-valve 34, having a weighted stem 35. A piston 38 is formed upon this valvestem and works in a small cylinder 36, entering the side wall of the casing 31. A set-nut 37, bored out to pass loosely over the valvestem, is introduced into the outer end of this cylinder and may be adjusted to limit the movement of the valve by engaging the face of the piston 38.

A web 42 crosses the passa e 22 to deflect the air into the chamber of t e casing 31 as it passes the fuel-valve to insure its becoming intimately admixed with the fuel at this point.

The engine-cylinder is provided with the usual exhaust-port 39, which is also uncovered by the piston 19 when near the limit of its outstroke, and a spark-plug 40 is introduced at the head of the cylinder, preferably through the side wall and in line with the admission-port 30. A baffle-plate 41 rises from the face of the piston 19 to direct the incoming charge in the direction of the spark-plug 40 and to prevent its sweeping across the cylinder and passing out the exhaust-port 39 with the spent charge of the previous stroke.

The operation of the engine is as follows: During the instroke of the piston a quantity of air is drawn into the crank-chamber through the ports 28 in the casing 24, the spring 27 yielding to the overbalancingpressure of the atmosphere on the outer face of the valve 25,caused by the formation of a partial vacuum in the crank-chamber behind the receding piston and permitting the valve to open. The instroke of the piston also compresses the explosive charge previously delivered to the engine-cylinder, and this is ignited at or near the end of such stroke by the spark-plug 40. A pipe from the fuel-supply is attached to the outer end of the tube- 32, and fuel, preferably gasolene, is delivered to the tube under pressure, the pressure being applied at the fuel-supply tank (not shown) by any of the means commonly em loyed for such purpose.

When tlie outstroke of the piston is begun, the valve 25 is immediately closed by the spring 27 and the charge of air thus confined within the crank-chamber is compressed by the advancing piston. The pressure thus produced bearing upon the under face of the piston 38 raises the needle-valve 34 and permits a supply of fuel to enter through the opening 33, and if it is a liquid fuel it trickles down over the inside of the casing 31. As soon as the piston has advanced far enough to uncover the cylinderports 30 and 39 the charge of air compressed in the crankchamber rushes through the passage 22 into the engine-cylinder, and there displaces the spent gases of the previous charge, which pass out through the exhaust-port 39. The web 42 deflects the air on its Way to the cylinder into the chamber of the casing 31 where it becomes carbureted by evaporating the iiquid fuel from the walls of the casing. The combined eii'ect of this web 42 and the baffleplate 41 on the face of the piston 1.9 is to give the charge of air a whir ing motion, so that it becomes intimately admixed with the fuel-vapor. The needle-valve 34 is closed by the weight of its stem 35, and the fuelsupply thereby cut off as soon as the pressure in the crank-chamber and passage 22 is relieved by the opening of the port 30.

The quantity of air admitted to the crankchamber at each stroke may be regulated by turning the damper 29 so as to vary the area of the port-openings 28 in the face of the casing 24, and it will be understood from the preceding description that if a sufficient amount is admitted to completely destroy the vacuum formed in the crank-chamber during the instroke of the piston a pressure will be produced therein as soon as the outstroke begins, and the valve 34 will therefore be opened at once. If, however, a less amount of air is admitted, no pressure will be produced in the crank-chamber to open the fuel-valve until the piston has advanced for a considerable part ofits outstroke, and a smaller quantity of fuel will have been delivered by the time the valve is closed at the end of the stroke, as previously described. In this way the invention provides a simple and efficient means for obtaining about the same proportion of air and fuel-vapor in the explosive mixture of different charges, varying in the total amounts of each, whereby the en ine may be governed by re ulating the v0 ume of the charge without 0 anging the ercentages of its ingredients. The lug 43, ormed on the damper 29, affords means for attaching a suitable controlling device, whether manual or automatic.

While I have shown and described a piston for controlling the valve 33, it is obvious that any plate attached to the valve and yielding to the pressure within the chamber will come within the scope of the invention.

I claim as my invention- 1. In a gas-engine, in combination, an we plosion-chamber having admission and exhaust ports, means for closing the ports, a compression-chamber delivering to the admission-port of the explosion-chamber, an air-induction port and a fuel-induction port entering the compression-chamber, a suction-opened spring-seated valve for the airinduction port, and a gravity-seated valve for the fuel-induction port adapted to be opened independently of the air-valve by pressure within the chamber.

2. In a gas-engine, in combination, an explosion-chamber having admission and exiaust ports, means for closing the ports, a compressiiiii-chamber delivering to the admission-port of the evplosion-chamber, an air-induction port and a fuel-induction port entering the compression-chamber, a suction-opened spring-seated valve for the airinduction ort, a damper for regulating the delivery 0 such port, and a gravity-seated valve for the fuel-induction port adapted to be opened independently of the air-valve by pressure Within the chamber.

3. In a gas-engine, in combination, an explosion-chamber, a compression-chamber, a

passage connecting the two chambers, an

air-in uction port entering the compressionchamber, a valve for such port, a fuel-induction port entering the passage, and a yieldingly-seated valve for the last'named port, a cylinder opening into the chamber and a piston movable within the cylinder and fixed to the stem of the last-named valve.

4. In a gas-engine, in combination, an explosion-chamber, a compression-chamber, a passage connecting the two chambers, an air-in uction port entering the compressionchamber, a valve for such port, a damper for regulating the delivery of such port, a fuelin uction port entering the passage, and a yieldingly-seated valve for the last-named port adapted to be opened by pressure within the passage independently of the airvalve.

5. In a gas-engine, in combination, an explosion-chamber having admission and exhaust ports, means for closing the ports, a compression-chamber delivering to the admission-port of the explosioli-chamber, an air-induction port and a fuel-induction port entering the eompressiiiii-chamber, a valve for the air-induction port, a chambered casin opening to the fuel-indmtion port, a tu e passing through the wall of the casing, an opening in the tube within the chamber of the casing, a cylinder formed in the wall ofthe casin a needle-valve for closing the 0 ening in t e tube, a piston on the stem of t e valve and working within the cylinder, and a set-nut entering the cylinder for limiting the movement of the valve.

BENJAMIN F. STEWART. Witnesses:

CHARLES B. GiLLsoN, E. M. KLATCIIER. 

